Re: [GIT PATCH] Remove devfs from 2.6.17

["H. Peter Anvin" <hpa@zytor.com>]

Samuel Thibault wrote:
> 
> There has been at least my complaint about udev not being able to
> auto-load modules on /dev entry lookup (28th March 2006):
> 
> « Given a freshly booted linux box, hence uinput is not loaded (why
> would it be, it doesn't drive any real hardware) ; what is the right
> way(tm) for an application to have the uinput module loaded, so that it
> can open /dev/input/uinput for emulating keypresses?
> 
> - With good-old static /dev, we could just open /dev/input/uinput
>   (installed by the distribution), and thanks to a
>   alias char-major-10-223 uinput
>   line somewhere in /etc/modprobe.d, uinput gets auto-loaded.
> 
> - With devfs, it doesn't look like it works (/dev/misc/uinput is not
>   present and opening it just like if it existed doesn't work). But I
>   read in archives that it could be feasible.
> 
> - With udev, this just cannot work. As explained in an earlier thread,
>   even using a special filesystem that would report the opening attempt
>   to udevd wouldn't work fine since udevd takes time for creating the
>   device, and hence the original program needs to be notified ; this
>   becomes racy.
> 

It would be nice if udev could be fed not just from the kernel, but from 
the repository of modules that are available for loading.  That may 
require additional module information.

	-hpa